First section of Posey Tube (automobile tunnel) between Oakland and Alameda, California floated into place.Oakland Tribune �Camera News� newsreel . Old-fashioned silent movie title card �4500 tons of concrete afloat in Bay! First 210 foot section of Estuary Tube leaves Hunters Point for Oakland�; second title card �A bulkhead is placed at each end of the section�; title card �A strange craft, indeed towed by three tug-boats�. 1920s.14:39:36:12 Strange shot of steamer passing Webster St. Bridge in San Francisco or Alameda; boats disappears to show enormous concrete piece of estuary tube passing Webster�s St. Bridge.